Compatibility with ES modules

.gitignore

@@ -1,2 +1,3 @@
 node_modules
 .DS_Store
+dist

index.d.ts

@@ -0,0 +1,257 @@
+export interface Assertion {
+  /**
+   * Check if the value is truthy
+   */
+  ok(): void
+
+  /**
+   * Creates an anonymous function which calls fn with arguments.
+   */
+  withArgs(...args: any[]): Expect
+
+  /**
+   * Assert that the function throws.
+   *
+   * @param {(error: any) => any} fn - callback to match error string against
+   */
+  throw(fn: (error: any) => void): void
+  /**
+   * Assert that the function throws.
+   *
+   * @param {RexExp} regexp - regexp to match error string against
+   */
+  throw(regexp: RegExp): void
+  /**
+   * Assert that the function throws.
+   */
+  throw(): void
+
+  /**
+   * Assert that the function throws.
+   *
+   * @param {(error: any) => any} fn - callback to match error string against
+   */
+  throwError(fn: (error: any) => void): void
+  /**
+   * Assert that the function throws.
+   *
+   * @param {RexExp} regexp - regexp to match error string against
+   */
+  throwError(regexp: RegExp): void
+  /**
+   * Assert that the function throws.
+   */
+  throwError(): void
+
+  /**
+   * Assert that the function throws.
+   *
+   * @param {(error: any) => any} fn - callback to match error string against
+   */
+  throwException(fn: (error: any) => void): void
+  /**
+   * Assert that the function throws.
+   *
+   * @param {RexExp} regexp - regexp to match error string against
+   */
+  throwException(regexp: RegExp): void
+  /**
+   * Assert that the function throws.
+   */
+  throwException(): void
+
+  /**
+   * Checks if the array is empty.
+   */
+  empty(): Assertion
+
+  /**
+   * Checks if the obj exactly equals another.
+   */
+  equal(obj: any): Assertion
+  /**
+   * Checks if the obj exactly equals another.
+   */
+  be(obj: any): Assertion
+
+  /**
+   * Checks if the obj sortof equals another.
+   */
+  eql(obj: any): Assertion
+
+  /**
+   * Assert within start to finish (inclusive).
+   *
+   * @param start
+   * @param finish
+   */
+  within(start: number, finish: number): Assertion
+
+  /**
+   * Assert typeof.
+   */
+  a(type: string): Assertion
+
+  /**
+   * Assert instanceof.
+   */
+  a(type: Function): Assertion
+
+  /**
+   * Assert typeof.
+   */
+  an(type: string): Assertion
+
+  /**
+   * Assert instanceof.
+   */
+  an(type: Function): Assertion
+
+  /**
+   * Assert typeof / instanceof.
+   */
+  an: An
+
+  /**
+   * Assert numeric value above n.
+   */
+  greaterThan(n: number): Assertion
+
+  /**
+   * Assert numeric value above n.
+   */
+  above(n: number): Assertion
+
+  /**
+   * Assert numeric value below n.
+   */
+  lessThan(n: number): Assertion
+
+  /**
+   * Assert numeric value below n.
+   */
+  below(n: number): Assertion
+
+  /**
+   * Assert string value matches regexp.
+   *
+   * @param regexp
+   */
+  match(regexp: RegExp): Assertion
+
+  /**
+   * Assert property "length" exists and has value of n.
+   *
+   * @param n
+   */
+  length(n: number): Assertion
+
+  /**
+   * Assert property name exists, with optional val.
+   *
+   * @param name
+   * @param val
+   */
+  property(name: string, val?: any): Assertion
+
+  /**
+   * Assert that string contains str.
+   */
+  contain(str: string): Assertion
+  string(str: string): Assertion
+
+  /**
+   * Assert that the array contains obj.
+   */
+  contain(obj: any): Assertion
+  string(obj: any): Assertion
+
+  /**
+   * Assert exact keys or inclusion of keys by using the `.own` modifier.
+   */
+  key(keys: string[]): Assertion
+  /**
+   * Assert exact keys or inclusion of keys by using the `.own` modifier.
+   */
+  key(...keys: string[]): Assertion
+  /**
+   * Assert exact keys or inclusion of keys by using the `.own` modifier.
+   */
+  keys(keys: string[]): Assertion
+  /**
+   * Assert exact keys or inclusion of keys by using the `.own` modifier.
+   */
+  keys(...keys: string[]): Assertion
+
+  /**
+   * Assert a failure.
+   */
+  fail(message?: string): Assertion
+
+  and: Assertion
+}
+
+interface Expect extends Assertion {
+  not: Not
+  to: To
+  only: Only
+  have: Have
+  be: Be
+}
+
+interface Not extends Assertion {
+  to: To
+  be: Be
+  have: Have
+  include: Include
+  only: Only
+}
+
+interface To extends Assertion {
+  be: Be
+  have: Have
+  include: Include
+  only: Only
+  not: Not
+}
+
+interface Only extends Assertion {
+  have: Have
+}
+
+interface Have extends Assertion {
+  own: Own
+}
+
+interface Be extends Assertion {
+  /**
+   * Checks if the obj exactly equals another.
+   */
+  (obj: any): Assertion
+
+  an: An
+}
+
+interface An extends Assertion {
+  /**
+   * Assert typeof.
+   */
+  an(type: string): Assertion
+
+  /**
+   * Assert instanceof.
+   */
+  an(type: Function): Assertion
+}
+
+interface Include extends Assertion {}
+
+declare var expect: {
+  (actual?: any, message?: string): Expect
+  version: string
+  stringify(value: any, showHidden?: boolean, depth?: number): string
+  eql(actual: any, expected: any): boolean
+}
+
+export { expect }
+export default expect